Low temperature stable concentrate containing fatty acid based composition and fuel composition and method thereof

ABSTRACT

A concentrate composition contains (A) a fatty carboxylic acid based composition selected from (1) a fatty monocarboxylic acid, (2) an ester of (A)(1), (3) an amide of (A)(1), (4) an amine salt of (A)(1), and (5) a mixture thereof, and (B) a low temperature stability improving amount of a composition comprising one or more low temperature stability improving compositions. A fuel composition contains a major amount of a fuel and a minor amount of the concentrate composition. A method to improve the lubricity of a fuel composition containing a fuel comprises adding a lubricity improving amount of the concentrate composition to the fuel. The low temperature stability improving composition (B) is very effective in maintaining clarity, homogeneity and fluidity of a concentrate composition containing a fatty carboxylic acid based composition at low temperatures.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention involves a low temperature stable concentrate composition that comprises a fatty carboxylic acid based composition. The concentrate composition is useful as an additive in numerous applications including fuels where it provides a fuel composition and a method in which the lubricity of the fuel composition is improved.

2. Description of the Related Art

Fatty carboxylic acid based compositions are useful as performance additives or processing aids in numerous applications to include paints, coatings, inks, metalworking fluids, hydraulic fluids, power transmission fluids, gear oils, internal combustion engine lubricants, and various manufacturing processes such as polymer processing.

Fatty carboxylic acid based compositions are especially useful as performance additives in fuel compositions for internal combustion engines to improve lubricity which is becoming an important performance issue in order to prevent premature failure of fuel pumps and injectors. Since sulfur components in petroleum based hydrocarbon fuels can poison engine exhaust treatment catalysts used in spark-ignited and compression-ignited internal combustion engines, exhaust emission regulations worldwide are requiring a gradual reduction in the sulfur content of petroleum based fuels which also reduces the lubricity of these fuels.

An effective way to provide a fatty carboxylic acid based composition as a performance additive and/or processing aid for various applications is in the form of a concentrate composition. This concentrate composition can have stability problems at low temperatures that result in transfer and/or handling difficulties due to a) nonhomogeneity evidenced by haze, flocculence, sedimentation, and phase separation and b) solidification. These low temperature stability problems can be improved upon by addition of a diluent to and/or heating the concentrate composition.

International Publication No. WO 01/38461 A1 discloses a composition comprising a fatty acid or derivative thereof and a flow improver to improve low temperature operability.

U.S. Pat. No. 5,413,725 discloses a composition comprising a triglyceride and at least one pour point depressant.

U.S. Pat. No. 6,017,370 discloses that the low temperature flow properties of wax-containing liquids are improved by adding a composition comprising a polymer of a C₈₋₂₀ alkyl ester of an ethylenically unsaturated 1,2-diacid and the reaction product of an alkanolamine with a C₈₋₅₀ hydrocarbyl-substituted acylating agent.

U.S. Pat. No. 3,250,715 discloses terpolymers of dialkyl fumarates, vinyl esters of fatty acids and alkyl vinyl ethers and lubricants comprising these terpolymers which possess low pour points.

U.S. Pat. No. 6,596,037 discloses low-temperature-stabilized fatty acid mixtures comprising at least one C₆₋₅₀ saturated mono- or dicarboxylic acid, at least one C₆₋₅₀ unsaturated mono- or dicarboxylic acid, and copolymers comprising 1) bivalent units that are derivatives of maleic, fumaric or itaconic acid, 2) bivalent units that are derived from vinyl, acrylic or methacrylic acid esters, and optionally 3) bivalent units derived from polyolefins.

The present invention involves a concentrate composition comprising a fatty carboxylic acid based composition that is treated with a low temperature improving amount of a composition that significantly improves low temperature stability of the concentrate composition, the improvement being synergistic or unexpected in some instances. The low temperature stabilized concentrate composition of the present invention does not require addition of large amounts of diluent and/or a means of heating to overcome low temperature stability problems.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a concentrate composition comprising a fatty carboxylic acid based composition wherein the concentrate composition has low temperature stability.

Another object of this invention is to provide a fuel composition comprising a fuel in which the fuel composition has improved lubricity.

A further object of the invention is to provide a fuel composition comprising a gasoline in which the fuel composition has improved lubricity.

A still further object of the present invention is to provide a fuel composition comprising a diesel fuel in which the fuel composition has improved lubricity.

Yet a further object of the present invention is to provide a fuel composition comprising a nonhydrocarbon fuel in which the fuel composition has improved lubricity.

Additional objects and advantages of the present invention will be set forth in the Detailed Description which follows and, in part, will be obvious from the Detailed Description or may be learned by the practice of the invention. The objects and advantages of the invention may be realized by means of the instrumentalities and combinations pointed out in the appended claims.

To achieve the foregoing objects in accordance with the present invention as described and claimed herein, a concentrate composition comprises (A) a fatty carboxylic acid based composition selected from the group consisting of (1) a fatty monocarboxylic acid, (2) an ester of (A)(1), (3) an amide of (A)(1), (4) an amine salt of (A)(1), and (5) a mixture thereof; and (B) a low temperature stability improving amount of a composition comprising (1) a copolymer of ethylene and an unsaturated ester of a monocarboxylic acid; and (2) a composition selected from the group consisting of (a) a nitrogen-containing esterified copolymer of a C₂ to C₃₀ alkene or a vinyl substituted aromatic compound and an alpha, beta unsaturated dicarboxylic acylating agent wherein at least 90% of the carbonyl groups of the copolymer of (B)(2)(a) are esterified, and 1 to 10% of the carbonyl groups of the copolymer of (B)(2)(a) are reacted with an amine having one primary or secondary amino group, (b) a copolymer of an unsaturated ester of a monocarboxylic acid and an alpha, beta unsaturated dicarboxylic acylating agent wherein at least 90% of the carbonyl groups of the acylating agent of the (B)(2)(b) copolymer are esterified, (c) a copolymer of an unsaturated ester of a monocarboxylic acid, an alpha, beta unsaturated dicarboxylic acylating agent and an alkenyl alkyl ether wherein at least 90% of the carbonyl groups of the acylating agent of the (B)(2)(c) copolymer are esterified, and (d) mixtures thereof wherein the weight ratio of (B)(1) to (B)(2) is 0.1:1 to 1:0.1.

In another embodiment of the invention a fuel composition comprises a major amount of a fuel and a minor amount of the above described concentrate composition that comprises component (A) and subcomponents (B)(1) and (B)(2).

An additional embodiment of the present invention is a method to improve the lubricity of a fuel composition comprising a fuel comprising adding to the fuel a lubricity improving amount of the above described concentrate composition that comprises component (A) and subcomponents (B)(1) and (B)(2).

In a further embodiment of the invention a concentrate composition comprises as described above component (A) which is selected from the group consisting of (A)(1), (A)(3), (A)(4), and a mixture thereof, and component (B) which is (B)(2)(a).

In yet another embodiment of this invention a fuel composition comprises a major amount of a fuel and a minor amount of the above described concentrate composition that comprises component (A) which is selected from (A)(1), (A)(3), (A)(4), and a mixture thereof, and component (B) which is (B)(2)(a).

In still another embodiment of the invention a method to improve the lubricity of a fuel composition comprising a fuel comprises adding to the fuel a lubricity improving amount of the above described concentrate composition that comprises component (A) which is selected from (A)(1), (A)(3), (A)(4), and a mixture thereof, and component (B) which is (B)(2)(a).

An embodiment of the present invention is a concentrate composition comprising as described above component (A) which is selected from the group consisting of (A)(1), (A)(2), (A)(3), (A)(4), and (A)(5), and component (B) which is (B)(2)(c).

In a further embodiment of the invention a fuel composition comprises a major amount of a fuel and a minor amount of the above described concentrate composition comprising component (A) which is selected from (A)(1), (A)(2), (A)(3), (A)(4), and (A)(5), and component (B) which is (B)(2)(c).

Another embodiment of this invention is a method to improve the lubricity of a fuel composition that comprises a fuel comprising adding a lubricity improving amount of the above described concentrate composition that comprises component (A) which is selected from (A)(1), (A)(2), (A)(3), (A)(4), and (A)(5), and component (B) which is (B)(2)(c).

DETAILED DESCRIPTION OF THE INVENTION

A concentrate composition of the present invention comprises (A) a fatty carboxylic acid based composition selected from the group consisting of (1) a fatty monocarboxylic acid, (2) an ester of the fatty monocarboxylic acid (A)(1), (3) an amide of the fatty monocarboxylic acid (A)(1), (4) an amine salt of the fatty monocarboxylic acid (A)(1), and (5) a mixture thereof; and (B) a low temperature stability improving amount of a composition comprising (1) a copolymer of ethylene and an unsaturated ester of a monocarboxylic acid; and (2) a composition selected from the group consisting of (a) a nitrogen-containing esterified copolymer of a C₂ to C₃₀ alkene or a vinyl substituted aromatic compound and an alpha, beta unsaturated dicarboxylic acylating agent wherein at least 90% of the carbonyl groups of the copolymer of (B)(2)(a) are esterified, and 1 to 10% of the carbonyl groups of the copolymer of (B)(2)(a) are reacted with an amine having one primary or secondary amino group, (b) a copolymer of an unsaturated ester of a monocarboxylic acid and an alpha, beta unsaturated dicarboxylic acylating agent wherein at least 90% of the carbonyl groups of the acylating agent of the (B)(2)(b) copolymer are esterified, (c) a copolymer of an unsaturated ester of a monocarboxylic acid, an alpha, beta unsaturated dicarboxylic acylating agent and an alkenyl alkyl ether wherein at least 90% of the carbonyl groups of the acylating agent of the (B)(2)(c) copolymer are esterified, and (d) mixtures thereof wherein the weight ratio of (B)(1) to (B)(2) is 0.1:1 to 1:0.1.

The fatty monocarboxylic acid (A)(1) of this invention can have 4 to 30 carbon atoms and in other instances can have 4 to 22 carbon atoms, 8 to 22 carbon atoms, and 12 to 22 carbon atoms. The fatty monocarboxylic acid can be a single acid having a certain number of carbon atoms or a mixture of two or more acids where each acid has a different number of carbon atoms. The fatty monocarboxylic acid can be linear, branched or a mixture thereof. The fatty monocarboxylic acid can be saturated, unsaturated or a mixture thereof. The fatty monocarboxylic acid can be obtained from a plant or animal source to include the fatty acids that are obtained from vegetable oils and animal fats. Useful examples of the fatty monocarboxylic acid include butyric acid, lauric acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, behenic acid, triacontanoic acid, and tall oil fatty acids. The (A)(1) fatty monocarboxylic acids of the present invention are available commercially from numerous suppliers including Arizona Chemical, Unichema and Henkel. In an embodiment of the invention the fatty monocarboxylic acid (A)(1) is a tall oil fatty acid, and in another embodiment of the invention the fatty carboxylic acid based composition (A) is (A)(1) as described hereinabove.

The ester (A)(2) of the present invention of the fatty monocarboxylic acid (A)(1) can be an ester from a monohydric alcohol, a polyhydric alcohol, or a mixture thereof. The monohydric alcohol can have 1 to 30 carbon atoms, can be branched or linear or a mixture thereof, and can be saturated or unsaturated or a mixture thereof. Useful examples of monohydric alcohols include methanol, ethanol, 1- and 2-propanol, butanol, amyl alcohol, 2-ethyl-1-hexanol, isooctanol and decanol. The polyhydric alcohol can have two or more hydroxyl groups and includes diols such as ethylene glycol, triols such as glycerol, polyglycols such as di(ethylene glycol) and poly(ethylene glycol)s of various molecular weights, mono- and dipentaerythritol, and hydrogenated saccharides such as sorbitol. Useful examples of the ester (A)(2) of the fatty monocarboxylic acid (A)(1) include mono- and/or di- and/or triglycerides of various fatty acids such as glycerol monooleate, methyl esters of various fatty acids such as the methyl ester of the fatty acids from rapeseed oil, and mono- and polycarboxylate esters of pentaerythritol or sorbitol such as esters of tall oil fatty acids and pentaerythritol and sorbitan monooleate. The (A)(2) esters of the present invention are available commercially from numerous suppliers.

The amide (A)(3) and the amine salt (A)(4) of the present invention can be formed from a reaction of an amine and the fatty monocarboxylic acid (A)(1). The amine can have 1 to 30 carbon atoms and includes ammonia. The amine can be a monoamine having one amino group or a polyamine having two or more amino groups in which the amino groups can be primary, secondary or tertiary with amines used to form the amide (A)(3) requiring at least one primary or secondary amino group in the amine. The amine can also be an alkanolamine and includes monoamines and polyamines having one or more hydroxyl groups. Useful examples of the amine used to form the amide (A)(3) and/or the amine salt (A)(4) include ammonia, butylamine, octylamine, oleylamine, octadecylamine, ethylenediamine, N-lauryl-1,3-propanediamine, ethanolamine, diethanolamine, triethanolamine, tris(hydroxymethyl)aminomethane, diethoxylated tallowamine, and 2-(2-aminoethylamino)ethanol. Methods to prepare amides and amine salts are well known and generally involve heating a mixture of amine and carboxylic acid at 120-200° C. while removing reaction water to form an amide and heating a mixture of amine and carboxylic acid at 20-100° C. to form an amine salt. Useful examples of the amide (A)(3) and amine salt (A)(4) of the present invention include oleamide, stearamide, and the amine salt of butylamine and oleic acid.

The fatty carboxylic acid based composition (A) of the present invention can be a mixture (A)(5) of the subcomponents (A)(1), (A)(2), (A)(3) and (A)(4). The mixture (A)(5) can include two or more subcomponents from the same subcomponent type such as two different fatty monocarboxylic acids from subcomponent (A)(1) or can include one or more subcomponents from each of two or more different subcomponent types such as a fatty monocarboxylic acid from subcomponent (A)(1) and an amide from subcomponent (A)(3).

The low temperature stability improving composition (B) of the present invention can comprise (B)(1) which is a copolymer of ethylene and an unsaturated ester of a monocarboxylic acid. The unsaturated ester of the copolymer of (B)(1) can be viewed as being composed of a monocarboxylic acid portion RCO₂H and an alcohol portion R′OH which combine with loss of water to form the ester RCO₂R′. The unsaturated ester of the monocarboxylic acid can be unsaturated in the monocarboxylic acid portion of the ester, in the alcohol portion of the ester, or in a mixture thereof. Both the monocarboxylic acid and alcohol portion of the unsaturated ester can have 1 to 22 carbon atoms, and in other instances can have 2 to 16 carbon atoms and 2 to 10 carbon atoms except that the unsaturated portion of the ester will have at least two carbon atoms when present in the alcohol portion of the ester and at least three carbon atoms when present in the acid portion of the ester. The unsaturated ester of the monocarboxylic acid can be a mixture of esters where each ester has a different number of carbon atoms. Both the alcohol and monocarboxylic acid portion of the unsaturated ester can be linear, branched, or a mixture thereof. Useful examples of the unsaturated ester of the monocarboxylic acid include vinyl acetate, allyl acetate, isopropenyl acetate, vinyl propionate, methyl acrylate, ethyl acrylate, methyl methacrylate, and methyl crotonate. The copolymer (B)(1) can be prepared by well known methods to include by a free radical polymerization of ethylene and the unsaturated ester of the monocarboxylic acid. Copolymers of ethylene and the unsaturated ester of the monocarboxylic acid such as ethylene-vinyl acetate copolymers are also commercially available from various suppliers including Octel Starreon and Millennium Petrochemicals. In an embodiment of the invention the copolymer (B)(1) is a copolymer of ethylene and vinyl acetate where the copolymer has a 5 to 40 mole % vinyl acetate content, and in other instances has a 5 to 30 and a 10 to 20 mole % vinyl acetate content. This ethylene-vinyl acetate copolymer can have a number average molecular weight ranging from 1,000 to 10,000, and in other instances ranging from 1,500 to 5,000 and from 1,800 to 3,000.

The low temperature stability improving composition (B) of the present invention can comprise a composition (B)(2) which can be (B)(2)(a) a nitrogen-containing esterified copolymer of a C₂ to C₃₀ alkene or a vinyl substituted aromatic compound and an alpha, beta unsaturated dicarboxylic acylating agent. The alkene can be an alpha-olefin, an internal olefin, or a mixture thereof. The alkene can be linear, branched, or a mixture thereof. The vinyl substituted aromatic compound can include styrene, alpha-methylstyrene and beta-methylstyrene. The alpha, beta unsaturated dicarboxylic acylating agent includes acids and derivatives thereof to include anhydrides and esters. Useful examples of the alpha, beta unsaturated dicarboxylic acylating agent include maleic acid or a derivative thereof such as maleic anhydride, fumaric acid or a derivative thereof such as dimethyl fumarate, itaconic acid or a derivative thereof such as itaconic anhydride, and citraconic acid or a derivative thereof such as citraconic anhydride. In an embodiment of the invention the copolymer of (B)(2)(a) can contain a third monomer which can include an alkyl methacrylate, an alkyl acrylate, or a vinyl alkyl ether. The mole ratio in the copolymer of (B)(2)(a) of the alkene-or vinyl-substituted aromatic compound to the alpha, beta unsaturated dicarboxylic acylating agent can be 0.25:1 to 1:0.25, and in other instances can be 0.5:1 to 1:0.5, 0.75:1 to 1:0.75, 0.9:1 to 1:0.9, and 1:1. The molecular weight of the copolymer of (B)(2)(a) prior to esterification and reaction with an amine can be given in terms of a reduced specific viscosity which can range from 0.05 to 2, and in other instances from 0.1 to 1, 0.25 to 0.85, 0.3 to 0.8, and 0.5 to 0.9. The reduced specific viscosity of a polymer and its relation to the molecular weight of that polymer are defined and described in U.S. Pat. No. 5,413,725 and in “Principles of Polymer Chemistry”, Paul J. Flory, 1953 edition, page 308 and following pages. In an embodiment of the invention at least 90% of the carbonyl groups of the copolymer of (B)(2)(a) can be esterified, and in other embodiments at least 92% and at least 94% of the carbonyl groups can be esterified. In another embodiment of the invention the carbonyl groups of the copolymer of (B)(2)(a) can be esterified with a mixture of alcohols comprising short chain length alcohols having 5 or less carbon atoms, intermediate chain length alcohols having 6-10 carbon atoms, and long chain length alcohols having 12 or more carbon atoms. In other embodiments of the invention the short chain length alcohols can be an alcohol or mixture of alcohols taken from C₁ to C₅ alcohols, C₂ to C₅ alcohols, and C₃ to C₅ alcohols; the intermediate chain length alcohols can be an alcohol or mixture of alcohols taken from C₆ to C₁₀ alcohols, C₆ to C₈ alcohols, and C₈ to C₁₀ alcohols; the long chain length alcohols can be an alcohol or mixture of alcohols taken from C₁₂ to C₃₀ alcohols, C₁₂ to C₂₂ alcohols, and C₁₂ to C₂₀ alcohols. In another embodiment of the invention 1 to 10% of the carbonyl groups of the copolymer of (B)(2)(a) can be reacted with an amine, and in other instances 2 to 8% and 3 to 6% of the carbonyl groups can be reacted with an amine. The amine of the present invention has one primary or secondary amino group and can be a monoamine or a polyamine. Useful examples of the amine include ammonia, butylamine, diethylamine, N,N-dimethylethylenediamine, N,N-dimethyl-N′-ethylethylenediamine, and aminoalkyl-substituted heterocyclic compounds such as the N-aminoalkyl-substituted nitrogen heterocyclic compounds 4-(3-aminopropyl)morpholine and 1-(2-aminoethyl)piperidine. In an embodiment of the invention the equivalent ratio of the carbonyl groups of the copolymer of (B)(2)(a) to the short chain length alcohols, the intermediate chain length alcohols, the long chain length alcohols, and the amine can be 1:0.03-0.3:0.1-0.8:0.1-0.8:0.01-0.1, and in other embodiments the equivalent ratio can be 1:0.04-0.25:0.2-0.7:0.2-0.7:0.02-0.08; 1:0.04-0.21 :0.25-0.65:0.25-0.65:0.03-0.06; and 1:0.1-0.3:0.2-0.4:0.5-0.7:0.03-0.06. The nitrogen-containing esterified copolymer (B)(2)(a) of the present invention can be prepared by a free radical polymerization of its constituent monomers to form the copolymer followed by esterification with alcohols and reaction with an amine to functionalize the pendant carbonyl groups. In an embodiment of the invention the nitrogen containing esterified copolymer (B)(2)(a) is prepared by polymerizing maleic anhydride and styrene, esterifying the copolymer with a mixture of short chain, intermediate chain and long chain alcohols, and reacting the unesterified carbonyl groups of the copolymer with an amine containing one primary or secondary amino group as described in U.S. Pat. No. 5,413,725. In another embodiment of the invention the copolymer of (B)(2)(a) is copolymer of maleic anhydride and styrene which copolymer prior to esterification has a reduced specific viscosity of 0.1 to 1 and after esterification is reacted with an amine which is an aminoalkyl-substituted heterocyclic compound. In a further embodiment of this invention the composition (B)(2) is (B)(2)(a) as described hereinabove.

The low temperature stability improving composition (B) of this invention can comprise (B)(2)(b) which is a copolymer of an unsaturated ester of a monocarboxylic acid and an alpha, beta unsaturated dicarboxylic acylating agent. The unsaturated ester of the monocarboxylic acid of the copolymer of (B)(2)(b) can be the same as the unsaturated ester of the monocarboxylic acid of the copolymer of (B)(1) described above. The alpha, beta unsaturated dicarboxylic acylating agent of the copolymer of (B)(2)(b) can be the same as the alpha, beta unsaturated dicarboxylic acylating agent of the copolymer of (B)(2)(a) described above. The mole ratio of the monomers of the copolymer of (B)(2)(b) of the invention can be 0.25:1 to 1:0.25, and in other instances can be 0.5:1 to 1:0.5, 0.75:1 to 1:0.75, 0.9:1 to 1:0.9, and 1:1. The dicarboxylic acylating agent can be esterified prior to the polymerization to form the (B)(2)(b) copolymer or can be esterified or transesterified following the polymerization to form the (B)(2)(b) copolymer. In an embodiment of the invention the dicarboxylic acylating agent can be 50 to 100% esterified, and in other embodiments can be at least 70%, at least 80%, at least 90%, or at least 95% esterified. In an embodiment of the invention the dicarboxylic acylating agent is esterified with a mixture of alcohols having 8 to 30 carbon atoms, and in other embodiments the mixture of alcohols has 8 to 26 carbon atoms, 10 to 24 carbon atoms, and 10 to 22 carbon atoms. The number average molecular weight of the copolymer (B)(2)(b) of this invention can range from 5,000 to 200,000, and in other instances can range from 10,000 to 100,000, and 15,000 to 75,000. Methods to prepare the (B)(2)(b) copolymer of this invention are well known and include esterifying the dicarboxylic acylating agent followed by a free radical polymerization of the esterified dicarboxylic acylating agent and the unsaturated ester of the monocarboxylic acid. In an embodiment of the invention the copolymer (B)(2)(b) is a copolymer of a vinyl carboxylate ester and an ester of an alpha, beta unsaturated dicarboxylic acid. In another embodiment of this invention the copolymer (B)(2)(b) is a copolymer of vinyl acetate and a fumarate ester where the fumarate ester is prepared from a mixture of alcohols having 8 to 30 carbon atoms as described in U.S. Pat. No. 6,017,370, and in a further embodiment of the invention (B)(2) is (B)(2)(b) as described hereinabove.

The low temperature stability improving composition (B) of the present invention can comprise (B)(2)(c) which is a copolymer of an unsaturated ester of a monocarboxylic acid, an alpha, beta unsaturated dicarboxylic acylating agent and an alkenyl alkyl ether. The unsaturated ester of the monocarboxylic acid of the copolymer of (B)(2)(c) can be the same as described above for the unsaturated ester of the monocarboxylic acid of the (B)(1) copolymer. The alpha, beta unsaturated dicarboxylic acylating agent of the copolymer of (B)(2)(c) can be the same as described above for the alpha, beta unsaturated dicarboxylic acylating agent of the copolymer of (B)(2)(a). The alkenyl alkyl ether of this invention can have an alkyl group that has 1 to 18 carbon atoms, and in other instances 1 to 10 carbon atoms, and 1 to 6 carbon atoms. The alkenyl alkyl ether of the invention has an alkenyl group with an unsaturated carbon to carbon double bond that can have 2 to 18, 2 to 10, and 2 to 6 carbon atoms. Useful examples of the alkenyl alkyl ether include alkyl vinyl ethers such as ethyl, propyl, butyl, pentyl and hexyl vinyl ether as well as allyl ethyl ether and 1-butenyl ethyl ether. In an embodiment of the invention the alkenyl alkyl ether is a mixture of two or more alkenyl alkyl ethers. The mole ratio in the copolymer (B)(2)(c) of the alpha, beta unsaturated dicarboxylic acylating agent to the combination of the unsaturated ester of the monocarboxylic acid and the alkenyl alkyl ether can be 0.25:1 to 1:0.25, and in other instances can be 0.5:1 to 1:0.5, 0.75:1 to 1:0.75, 0.9:1 to 1:0.9, and 1:1. The mole ratio in the copolymer (B)(2)(c) of the unsaturated ester of the monocarboxylic acid to the alkenyl alkyl ether can be 0.1:1 to 1:0.1, and in other instances can be 0.4:1 to 1:0.4, 0.6:1 to 1:0.6, 0.9:1 to 1:0.9, and 1:1. The alpha, beta unsaturated dicarboxylic acylating agent can be esterified before or can be esterified or transesterified after the polymerization to form the (B)(2)(c) copolymer. In an embodiment of the invention the alpha, beta unsaturated dicarboxylic acylating agent can be 50 to 100% esterified, and in other embodiments can be at least 70%, at least 80%, at least 90%, and at least 95% esterified. The alpha, beta unsaturated dicarboxylic acylating agent of the (B)(2)(c) copolymer can be esterified with a mixture of alcohols having 8 to 30 carbon atoms, and in other instances having 8 to 22 carbon atoms, and 10 to 18 carbon atoms. The molecular weight of the copolymer (B)(2)(c) of this invention is directly proportional to the specific viscosity of the copolymer as described in U. S. Pat. No. 3,250,715. The molecular weight of the copolymer (B)(2)(c) can be defined in terms of its specific viscosity which can range from 0.05 to 2, and in other instances can range from 0.09 to 0.8, and 0.2 to 0.6. In an embodiment of the invention the number average molecular weight of the copolymer (B)(2)(c) can range from 1,000 to 50,000, and in other instances can range from 2,000 to 25,000, and 3,000 to 15,000. Methods to prepare the (B)(2)(c) copolymer of this invention are well known and include an acid catalyzed esterification of the alpha, beta unsaturated dicarboxylic acylating agent and then a free radical polymerization of the esterified alpha, beta unsaturated dicarboxylic acylating agent, the unsaturated ester of the monocarboxylic acid and the alkenyl alkyl ether. In an embodiment of the invention the copolymer (B)(2)(c) is a copolymer of a fumarate ester, vinyl acetate and an alkyl vinyl ether such as ethyl vinyl ether as described in U.S. Pat. No. 3,250,715 where the fumarate ester is prepared from a mixture of alcohols having 8 to 30 carbon atoms, and in a further embodiment of the invention (B)(2) is (B)(2)(c) as described hereinabove.

The concentrate composition of the present invention contains a low temperature stability improving amount of a composition which is component (B) as described throughout this application. Component (B) improves the low temperature stability of the concentrate composition which contains a fatty carboxylic acid based composition. Component (B) improves the low temperature stability of the concentrate composition by maintaining or tending to maintain the clarity, homogeneity and fluidity of the concentrate composition at a low temperature as opposed to unstable compositions that can display haze, flocculence, sedimentation, phase separation and solidification. Component (B) tends to maintain low temperature stability of the concentrate composition by allowing less deterioration of clarity, homogeneity and fluidity at a low temperature compared to an untreated fatty carboxylic acid based composition. A low temperature is generally at or below 20° C., and in other instances at or below 0° C., −18° C., and −40° C. The low temperature stability of the concentrate composition of the present invention facilitates transferring and/or handling a fatty carboxylic acid based composition at low temperatures.

The concentrate composition of the present invention can comprise component (A) as described above, component (B) which can comprise subcomponents (B)(1) and/or (B)(2) as described throughout this application, optionally a diluent (C) as described below, and optionally one or more performance additives (D) as described below. Component (A) can be present in the concentrate composition at 1 to 99.5% by weight, and in other embodiments at 50 to 99% by weight, and at 60 to 99% or 60 to 95% by weight. The weight ratio of subcomponents (B)(1) to (B)(2) in the concentrate composition can be 0.1:1 to 1:0.1, and in other embodiments can be 0.25:1 to 1:0.25, 0.5:1 to 1:0.5, 0.75:1 to 1:0.75, 0.9:1 to 1:0.9, and 1:1. Each of the subcomponents (B)(1) and (B)(2) can be present in the concentrate composition at 0.001 to 10% by weight, and in other embodiments at 0.01 to 10% by weight, at 0.03 to 5% by weight, and at 0.05 to 4% by weight. The diluent (C) can be present in the concentrate composition from none to 50% by weight, and in other instances at 1 to 40% by weight, and at 5 to 30% by weight. The one or more performance additives (D) can be present in the concentrate composition from none to 90% by weight, and in other instances at 0.0001 to 70% by weight, at 0.0001 to 50% by weight, and at 0.0001 to 30% by weight.

The concentrate composition of the present invention, comprising component (A) and subcomponents (B)(1) and/or (B)(2), can further comprise (C) a diluent. The diluent can include a solvent, an oil of lubricating viscosity, or a mixture thereof. The solvent can include an aliphatic hydrocarbon, an aromatic hydrocarbon, an alcohol, or a mixture thereof. The aliphatic hydrocarbon includes paraffinic naphthas, low aromatic content kerosenes, or mixtures thereof. The aromatic hydrocarbon includes aromatic naphthas, toluene, xylenes, or mixtures thereof. The oil of lubricating viscosity can include a natural oil, a synthetic oil, or a mixture thereof. The natural oil includes petroleum based mineral oils, vegetable oils, animal oils, or mixtures thereof. The synthetic oil includes polyolefins such as a poly(alpha-olefin) and/or an olefin copolymer, esters of mono- and/or polycarboxylic acids and mono- and/or polyhydric alcohols, alkylated aromatics such as an alkylated benzene, or mixtures thereof.

The concentrate composition of the present invention, comprising component (A) and subcomponents (B)(1) and/or (B)(2), can further comprise (D) one or more performance additives. The performance additive or additives included in the concentrate composition will generally depend on the application that the concentrate composition is to be used for. A concentrate composition of the present invention intended for use in a fuel composition can further comprise one or more performance additives that are generally fuel additives to include nitrogen-containing detergents, amine-containing polyethers, metal-containing detergents, antioxidants such as hindered phenols, rust inhibitors such as alkenylsuccinic acids, corrosion inhibitors such as alkylamines, combustion improvers such as nitroalkanes, demulsifiers, antifoaming agents, valve seat recession additives, metal deactivators, supplementary lubricity agents, bacteriostatic agents, gum inhibitors, anti-icing agents, anti-static agents, organometallic fuel-borne catalysts for improved combustion performance, supplementary low temperature flow improvers, and fluidizers such as mineral oils, polyolefins and polyethers.

The concentrate composition in an embodiment of the invention comprises the components and subcomponents, as described throughout this application, (A) a fatty carboxylic acid based composition, (B)(1) which is a copolymer of ethylene and an alkenyl carboxylate ester, and (B)(2)(a) where the copolymer of (B)(2)(a) can be a copolymer of styrene and maleic anhydride. In another embodiment of the present invention the concentrate composition comprises the subcomponents, as described throughout the application, (A)(1) a fatty monocarboxylic acid which can be a tall oil fatty acid, (B)(1) which is a copolymer of ethylene and a vinyl carboxylate ester which can be vinyl acetate, and (B)(2)(a) which is a copolymer of styrene and maleic anhydride that is esterified with a mixture of alcohols and reacted with an aminoalkyl-substituted heterocyclic compound.

The concentrate composition in an embodiment of the invention comprises the components and subcomponents, as described throughout this application, (A) a fatty carboxylic acid based composition, (B)(1) which is a copolymer of ethylene and an alkenyl carboxylate ester, and (B)(2)(b) which is a copolymer of an alkenyl carboxylate ester and a fumarate ester. The concentrate composition in another embodiment of the invention comprises the subcomponents, as described throughout this application, (A)(1) a fatty monocarboxylic acid which can be a tall oil fatty acid, (B)(1) which is a copolymer of ethylene and a vinyl carboxylate ester which can be vinyl acetate, and (B)(2)(b) which is a copolymer of a vinyl carboxylate ester, which can be vinyl acetate, and a fumarate ester where the fumarate ester is prepared from a mixture of alcohols having 8 to 30 carbon atoms.

In an embodiment of the invention the concentrate composition comprises the components and subcomponents, as described throughout this application, (A) a fatty carboxylic acid based composition, (B)(1) which is a copolymer of ethylene and an alkenyl carboxylate ester, and (B)(2)(c) which is a copolymer of an alkenyl carboxylate ester, a fumarate ester and an alkenyl alkyl ether. The concentrate composition in another embodiment of the invention comprises the subcomponents, as described throughout this application, (A)(1) a fatty monocarboxylic acid which can be a tall oil fatty acid, (B)(1) which is a copolymer of ethylene and a vinyl carboxylate ester which can be vinyl acetate, and (B)(2)(c) which is a copolymer of a vinyl carboxylate ester, which can be vinyl acetate, and a fumarate ester and an alkyl vinyl ether which can be ethyl vinyl ether where the fumarate ester is prepared from a mixture of alcohols having 8 to 30 carbon atoms.

In another embodiment of the present invention the concentrate composition comprises the components and subcomponents, as described throughout this application, (A) which is selected from the group consisting of (A)(1), (A)(3), (A)(4), and a mixture thereof; (B) which is (B)(2)(a); optionally (C); and optionally (D). In a further embodiment of this invention the concentrate composition comprises the components and subcomponents, as described in this application, (A) which is (A)(1) which can be a tall oil fatty acid, and (B) which is (B)(2)(a) which is a copolymer of styrene and maleic anhydride that is esterified with a mixture of alcohols and reacted with an aminoalkyl-substituted nitrogen heterocyclic compound.

The concentrate composition in an embodiment of this invention comprises the components and subcomponents, as described in this application, (A) which is selected from the group consisting of (A)(1), (A)(2), (A)(3), (A)(4) and (A)(5); (B) which is (B)(2)(c); optionally (C); and optionally (D). In another embodiment of the invention the concentrate composition comprises components and subcomponents, as described in this application, (A) which is (A)(1) which can be a tall oil fatty acid, and (B) which is (B)(2)(c) which is a copolymer of an alkenyl carboxylate ester which can be vinyl acetate, a fumarate ester, and an alkyl vinyl ether which can be ethyl vinyl ether where the fumarate ester is prepared from a mixture of alcohols having 8 to 18 carbon atoms.

In an embodiment of the present invention a fuel composition comprises a major amount of a fuel; and a minor amount of a concentrate composition comprising the components and subcomponents, as described in this application, (A) which is selected from the group consisting of (A)(1), (A)(2), (A)(3), (A)(4), and (A)(5); (B) which comprises (B)(1) and (B)(2) which is selected from the group consisting of (B)(2)(a), (B)(2)(b), (B)(2)(c) and (B)(2)(d); optionally (C); and optionally (D). In another embodiment of this invention a fuel composition comprises a major amount of a fuel; and a minor amount of a concentrate composition comprising the components and subcomponents, as described in the application, (A) which is selected from (A)(1), (A)(3), (A)(4), and a mixture thereof; (B) which is (B)(2)(a); optionally (C); and optionally (D). In still another embodiment of the invention the fuel composition comprises (A) which is selected from (A)(1), (A)(3), (A)(4), and a mixture thereof; and (B) which is (B)(2)(a) where the copolymer of (B)(2)(a) is a maleic anhydride-styrene copolymer, the copolymer prior to esterification has a reduced specific viscosity of 0.25 to 0.85, and the copolymer is reacted with a N-aminoalkyl-substituted nitrogen heterocyclic compound. A further embodiment of the invention is a fuel composition comprising a major amount of a fuel; and a minor amount of a concentrate composition comprising the components and subcomponents, as described in the application, (A) which is selected from the group consisting of (A)(1), (A)(2), (A)(3), (A)(4) and (A)(5); (B) which is (B)(2)(c); optionally (C); and optionally (D). In still a further embodiment of this invention the fuel composition comprises (A) which is selected from (A)(1), (A)(2), (A)(3), (A)(4), and (A)(5); and (B) which is (B)(2)(c) where the copolymer of (B)(2)(c) is a copolymer of a fumarate ester, vinyl acetate and vinyl ethyl ether wherein the fumarate ester is prepared from a mixture of alcohols having 8 to 18 carbon atoms.

The fuel composition of this invention comprises a fuel comprising a hydrocarbon fuel, a nonhydrocarbon fuel, or a mixture thereof. The hydrocarbon fuel can be a petroleum distillate to include a gasoline as defined by ASTM specification D4814 or a diesel fuel as defined by ASTM specification D975. The hydrocarbon fuel can be a hydrocarbon prepared by a gas to liquid process to include the Fischer-Tropsch Process, the Lurgi Process, the Oil/Gas Process, and the SASOL Process. The nonhydrocarbon fuel can be an oxygen-containing composition to include an alcohol, an ether, a nitroalkane, or a mixture thereof. The nonhydrocarbon fuel can be an oxygenated derivative of a hydrocarbon prepared by a gas to liquid process to include those listed above for hydrocarbon fuels such as the Fischer-Tropsch Process. Useful nonhydrocarbon fuels include methanol, ethanol, dimethyl ether, diethyl ether, methyl t-butyl ether, and nitromethane. Useful mixtures of fuels include a mixture of hydrocarbon fuels such as a mixture of a petroleum distillate and a gas to liquid process hydrocarbon, a mixture of nonhydrocarbon fuels such as a mixture of ethanol and methanol, and a mixture of hydrocarbon and nonhydrocarbon fuels such as a mixture of gasoline and ethanol and/or methanol, a mixture of a diesel fuel and ethanol, and a mixture of a gas to liquid process hydrocarbon and an alcohol and/or an ether and/or a nitroalkane. In an embodiment of the invention the fuel is an emulsion of water in fuel that comprises a hydrocarbon fuel, a nonhydrocarbon fuel, or a mixture thereof as described hereinabove. This emulsion of water in fuel can be prepared by a mechanical mixing, by including one or more emulsifiers and/or surfactants in the emulsion, or by a combination of mechanical mixing and inclusion of emulsifiers and/or surfactants. The fuel can comprise a hydrocarbon fuel which has a reduced sulfur content. In an embodiment of the invention the fuel comprises a gasoline where the gasoline has a sulfur content at or below 1000 ppm by wt., and in other embodiments has a sulfur content at or below 150 ppm by wt., 80 ppm by wt., and 10 ppm by wt. where a fuel having a sulfur content below 10 ppm by wt. is considered essentially a sulfur-free fuel. In another embodiment of the invention the fuel comprises a diesel fuel where the diesel fuel has a sulfur content at or below 500 ppm by wt., and in other embodiments has a sulfur content at or below 350 ppm by wt., 80 ppm by wt., 30 ppm by wt., and 10 ppm by wt.

The fuel composition of the present invention contains a fatty carboxylic acid based concentrate composition comprising components and subcomponents, as described throughout this application, of (A), (B), optionally (C), and optionally (D). The fatty carboxylic acid based concentrate composition comprising components and subcomponents of (A) and (B) can be present in the fuel composition at 1-10,000 ppm by wt., and in other embodiments can be present at 1-1,000 ppm by wt., 5-600 ppm by wt., and 9-400 ppm by wt. Components (C) and (D) can be introduced into the fuel composition as separate components or as part of a concentrate composition to include as part of the concentrate composition of the present invention that contains a fatty carboxylic acid based composition. Component (C) can be present in the fuel composition from 1 to 5,000 ppm by weight. Component (D) can be present in the fuel composition depending on its function from 1-10,000 ppm by weight.

The concentrate composition and fuel composition of the present invention can be prepared by admixing the components at ambient to elevated temperatures up to 90° C. until the composition is homogeneous.

A method of the present invention to improve the lubricity of a fuel composition comprising a fuel of the present invention comprises adding a lubricity improving amount of a concentrate composition of the present invention to the fuel. In an embodiment of the invention the method to improve the lubricity of a fuel composition comprises adding to the fuel a concentrate composition comprising the components and subcomponents, as described in the application, (A) which is selected from (A)(1), (A)(2), (A)(3), (A)(4) and (A)(5); (B) which comprises (B)(1) and (B)(2) which is selected from (B)(2)(a), (B)(2)(b), (B)(2)(c) and (B)(2)(d); optionally (C); and optionally (D). In another embodiment of the invention the method to improve the lubricity of a fuel composition comprises adding to the fuel a concentrate composition comprising the components and subcomponents, as described in the application, (A) which is selected from (A)(1), (A)(3), (A)(4), and a mixture thereof; (B) which is (B)(2)(a); optionally (C); and optionally (D). In still another embodiment of the invention the method to improve the lubricity of a fuel composition comprises adding to the fuel a concentrate composition comprising the components and subcomponents, as described in the application, (A) which is selected from (A)(1), (A)(3), (A)(4), and a mixture thereof; and (B) which is (B)(2)(a) where the copolymer of (B)(2)(a) is a maleic anhydride-styrene copolymer, the copolymer prior to esterification has a reduced specific viscosity of 0.25 to 0.85, and the copolymer is reacted with a N-aminoalkyl-substituted nitrogen heterocyclic compound. In a further embodiment of the invention the method to improve the lubricity of a fuel composition comprises adding to the fuel a concentrate composition comprising components and subcomponents, as described in the application, (A) which is selected from (A)(1), (A)(2), (A)(3), (A)(4) and (A)(5); (B) which is (B)(2)(c); optionally (C); and optionally (D). In a still further embodiment of the invention the method to improve the lubricity of a fuel composition comprises adding to the fuel a concentrate composition comprising components and subcomponents, as described in the application, (A) which is selected from (A)(1), (A)(2), (A)(3), (A)(4) and (A)(5); and (B) which is (B)(2)(c) where the copolymer of (B)(2)(c) is a copolymer of a fumarate ester, vinyl acetate and vinyl ethyl ether wherein the fumarate ester is prepared from a mixture of alcohols having 8 to 18 carbon atoms. An embodiment of the invention of the method to improve the lubricity of a fuel composition comprises adding a concentrate composition of the present invention to a fuel comprising a hydrocarbon fuel that has a reduced sulfur content as described hereinabove. In an additional embodiment of the invention the method to improve the lubricity of a fuel composition comprises adding a concentrate composition of the present invention to a fuel comprising a hydrocarbon fuel that has a reduced sulfur content, as described hereinabove, wherein the fuel composition is used in an internal combustion engine equipped with an exhaust treatment device containing a catalyst that can be poisoned by sulfur. Exhaust treatment devices containing a catalyst that can be poisoned by sulfur include three-way catalytic converters and lean NO_(x) reduction catalysts.

The following examples demonstrate the effectiveness of the present invention in improving the low temperature stability of a concentrate composition that contains a fatty carboxylic acid based composition. The examples are provided to illustrate the invention and are not intended to limit the scope of the invention.

Low Temperature Storage Stability TABLE 1^(a) 28 Day Storage Day 1 Day 7 Day 14 Day 21 Day 28 Exam- Treatment^(b), 0° C./ 0° C./ 0° C./ 0° C./ 0° C./ ple % by wt −18° C. −18° C. −18° C. −18° C. −18° C. 1 None 1/4 1/7 1/— 1/— 1/— com- parative 2 0.25% EVA 1/1 1/2 1/3 1/3 1/3 com- parative 3  0.5% EVA 1/1 1/2 1/3 1/3 1/3 com- parative 4   1% EVA 1/1 1/1^(c) 1/1^(c) 1/3 1/3 com- parative 5   3% EVA 1/1 1/1^(c) 1/1^(c) 1/2^(c) 1/2^(c) com- parative 6 0.25% MS1 1/3 1/3 1/3 1/3 1/3 7 0.25% MS2 1/6 1/5 1/6 1/6 1/6 8 0.25% EVA + 1/1 1/1 1/1 1/1 111 0.25% MS1 9 0.25% EVA + 1/1 1/1 1/3 1/3 1/3 0.25% MS2 ^(a)Samples of untreated and treated concentrates containing a tall oil fatty acid were stored at 0° C. and −18° C. for 28 days and evaluated for low temperature stability at 1, 7, 14, 21 and 28 days. The untreated concentrate contained 72 wt. % tall oil fatty acid, 24 wt. % # polyisobutenylsuccinic acid which was 26 wt. % actives and 74 wt. % diluent, 1 wt. % demulsifier, and 3 wt. % C₈ amine. The compositions of the treated concentrates were the same as the composition for the untreated concentrate except that a treatment was added and the wt. of the tall oil fatty acid was reduced by an amount equal to the wt. of the # treatment. The following rating system was used to evaluate low temperature stability: 1 = clear, 2 = trace flocculence and/or slightly hazy, 3 = flocculent and/or hazy, 4 = heavy flocculence, 5 = opaque, 6 = heavy sediment, 7 = solidified. ^(b)Compositions of treatments were as follows: EVA was an ethylene-vinyl acetate copolymer containing 100% actives that was obtained from a supplier with a specification for vinyl acetate content of 35.5% by wt.; MS1 was a maleic anhydride-styrene copolymer having a reduced specific viscosity of 0.69 that was esterified with a mixture # of C₄, C₈₋₁₀ and C₁₂₋₁₈ alcohols and reacted with aminopropylmorpholine in a mole ratio of respectively copolymer carbonyl groups to alcohols to amine of 1:0.2:0.3:0.58:0.04 and that contained 35 wt. % actives; MS2 was a maleic anhydride-styrene copolymer having a reduced specific viscosity of 0.42 that was esterified with a mixture of C₄, C₈₋₁₀ and # C₁₂₋₁₈ alcohols and reacted with aminopropylmorpholine in a mole ratio of respectively copolymer carbonyl groups to alcohols to amine of 1:0.05:0.46:0.44:0.04 and that contained 48 wt. % actives. ^(c)Sample showed trace phase separation.

TABLE 2^(a) 72 Hour Storage Solvent^(b), Treatment^(c), Example wt % wt % 72 Hour @ −18° C.^(d) 1 comparative 15 — solid 2 comparative 20 — liq-10% opaq, 90% sl hazy 3 comparative 30 — liq-60% clear, 40% floc 4 comparative 10   3% EVA1 solid 5 —   2% FUM1 Liq-hazy, tr gel 6 10   2% FUM1 Liq-clear, tr gel 7 10 1.5% EVA1 + liq-sl hazy, tr gel 1.5% FUM2 8 10   2% EVA1 + 60% solid; 40% liq   1% FUM3 9 20   1% EVA1 + Liq-clear, tr gel   1% MS2 10 20 1.5% EVA1 + liq-sl hazy, tr gel 1.5% FUM2 11 20   2% EVA1 + liq-sl hazy, tr gel   1% FUM3 ^(a)Concentrate samples were prepared by adding to a tall oil fatty acid, as indicated in Table 2 based on wt % of the concentrate sample, a solvent, a low temperature stability improving treatment, or both a solvent and a low temperature stability improving # treatment. The concentrate samples were evaluated for low temperature stability after storage at −18° C. for 72 hours (3 days). ^(b)The solvent was an aromatic naphtha. ^(c)The compositions of the treatments were as follows: EVA1 was an ethylene-vinyl acetate copolymer composition obtained from a supplier that contained 50% by wt. actives and 50% by wt. aromatic solvent where the copolymer composition had a kinematic viscosity specification of less than 90 cSt at 50° C.; FUM1 was a fumarate # terpolymer composition containing 67% by wt. actives and 33% by wt. oil where the terpolymer had a number average molecular wt. between about 4,000 and 12,000 and was prepared by acid catalyzed esterification of 15.5 parts by wt. fumaric acid with 52.5 parts by wt. of a mixture of C₁₂₋₁₄ alcohols and a free radical polymerization of the fumarate # ester with 6.6 parts by wt. vinyl acetate and 3.7 parts by wt. vinyl ethyl ether; FUM2 was a fumarate copolymer composition containing 70% by wt. actives, 10% by wt. oil and 20% by wt. aliphatic naphtha where the copolymer had a number average molecular wt. between about 40,000 to 55,000 and was prepared by acid catalyzed esterification of 13.8 # parts by wt. fumaric acid with 53.8 parts by wt. of a mixture of C₁₂₋₁₈ alcohols and a free radical polymerization of the fumarate ester with 11.2 parts by wt. vinyl acetate; FUM3 was a fumarate copolymer composition containing 70% by wt. actives and 30% by wt. aliphatic naphtha where the copolymer had a number average molecular wt. between # about 20,000 to 30,000 and was prepared by acid catalyzed esterification of 12.9 parts by wt. fumaric acid with 45.4 parts by wt. of a mixture of C₁₂₋₁₈ alcohols and 7 parts by wt. of a mixture of C₁₈₋₂₂ alcohols and a free radical polymerization of the fumarate ester with 9.6 parts by wt. vinyl acetate; MS2 was the nitrogen-containing esterified maleic # anhydride-styrene copolymer described in Table1. ^(d)Abbreviations for the low temperature stability evaluations were as follows: liq = liquid, opaq = opaque, sl hazy = slightly hazy, floc = flocculent, tr gel = trace gel.

z,999 ach of the documents referred to in this Detailed Description of the Invention z,999 incorporated herein by reference. All numerical quantities in this application z,999 escribe or claim the present invention are understood to be modified by the word z,999 except for the examples or where explicitly indicated otherwise. All chemical z,999 s or contents throughout this application regarding the present invention are z,999 d to be as actives unless indicated otherwise even though diluents may be 

1. A concentrate composition, comprising: (A) a fatty carboxylic acid based composition selected from the group consisting of (1) a fatty monocarboxylic acid, (2) an ester of (A)(1), (3) an amide of (A)(1), (4) an amine salt of (A)(1), and (5) a mixture thereof; and (B) a low temperature stability improving amount of a composition comprising (1) a copolymer of ethylene and an unsaturated ester of a monocarboxylic acid; and (2) a composition selected from the group consisting of (a) a nitrogen-containing esterified copolymer of a C₂ to C₃₀ alkene- or a vinyl-substituted aromatic compound and an alpha, beta unsaturated dicarboxylic acylating agent wherein at least 90% of the carbonyl groups of the copolymer of (B)(2)(a) are esterified, and 1 to 10% of the carbonyl groups of the copolymer of (B)(2)(a) are reacted with an amine having one primary or secondary amino group, (b) a copolymer of an unsaturated ester of a monocarboxylic acid and an alpha, beta unsaturated dicarboxylic acylating agent wherein at least 90% of the carbonyl groups of the acylating agent of the (B)(2)(b) copolymer are esterified, (c) a copolymer of an unsaturated ester of a monocarboxylic acid, an alpha, beta unsaturated dicarboxylic acylating agent and an alkenyl alkyl ether wherein at least 90% of the carbonyl groups of the acylating agent of the (B)(2)(c) copolymer are esterified, and (d) mixtures thereof, wherein the weight ratio of (B)(1) to (B)(2) is 0.1:1 to 1:0.1.
 2. The concentrate composition of claim 1, further comprising: (C) a diluent.
 3. The concentrate composition of claim 1, further comprising: (D) one or more performance additives.
 4. The concentrate composition of claim 1 wherein component (A) is present at 50 to 99% by weight, the weight ratio of (B)(1) to (B)(2) is 0.5:1 to 1:0.5; and each of (B)(1) and (B)(2) is present at 0.01 to 10% by weight.
 5. The concentrate composition of claim 1 wherein component (A) is (A)(1) which is a tall oil fatty acid.
 6. The concentrate composition of claim 1 wherein (B)(1) is a copolymer of ethylene and vinyl acetate wherein the copolymer has a 5 to 40 mole % vinyl acetate content.
 7. The concentrate composition of claim 1 wherein (B)(2) is (B)(2)(a) in which the copolymer is a copolymer of maleic anhydride and styrene, the copolymer prior to esterification has a reduced specific viscosity of 0.1 to 1, and the amine is an aminoalkyl-substituted heterocyclic compound.
 8. The concentrate composition of claim 1 wherein (B)(2) is (B)(2)(b) in which the copolymer is a copolymer of a fumarate ester and vinyl acetate wherein the fumarate ester is prepared from a mixture of alcohols having 8 to 30 carbon atoms.
 9. The concentrate composition of claim 1 wherein (B)(2) is (B)(2)(c) in which the copolymer is a copolymer of a fumarate ester, vinyl acetate and a vinyl alkyl ether wherein the fumarate ester is prepared from a mixture of alcohols having 8 to 30 carbon atoms.
 10. A concentrate composition, comprising: (A) a fatty carboxylic acid based composition selected from the group consisting of (1) a fatty monocarboxylic acid, (3) an amide of (A)(1), (4) an amine salt of (A)(1), and a mixture thereof; and (B) a low temperature stability improving amount of a composition comprising (B)(2)(a) a nitrogen-containing esterified copolymer of a C₂ to C₃₀ alkene or a vinyl substituted aromatic compound and an alpha, beta unsaturated dicarboxylic acylating agent wherein at least 90% of the carbonyl groups of the copolymer of (B)(2)(a) are esterified, and 1 to 10% of the carbonyl groups of the copolymer of (B)(2)(a) are reacted with an amine having one primary or secondary amino group.
 11. A concentrate composition, comprising: (A) a fatty carboxylic acid based composition selected from the group consisting of (1) a fatty monocarboxylic acid, (2) an ester of (A)(1), (3) an amide of (A)(1), (4) an amine salt of (A)(1), and (5) a mixture thereof; and (B) a low temperature stability improving amount of a composition comprising (B)(2)(c) a copolymer of an unsaturated ester of a monocarboxylic acid, an alpha, beta unsaturated dicarboxylic acylating agent and an alkenyl alkyl ether wherein at least 90% of the carbonyl groups of the acylating agent of the (B)(2)(c) copolymer are esterified.
 12. A fuel composition, comprising: a major amount of a fuel; and a minor amount of the concentrate composition of claim
 1. 13. A fuel composition, comprising: a major amount of a fuel; and a minor amount of the concentrate composition of claim
 10. 14. A fuel composition, comprising: a major amount of a fuel; and a minor amount of the concentrate composition of claim
 11. 15. A method to improve the lubricity of a fuel composition comprising a fuel, comprising: adding a lubricity improving amount of the concentrate composition of claim 1 to the fuel.
 16. A method to improve the lubricity of a fuel composition comprising a fuel, comprising: adding a lubricity improving amount of the concentrate composition of claim 10 to the fuel.
 17. A method to improve the lubricity of a fuel composition comprising a fuel, comprising: adding a lubricity improving amount of the concentrate composition of claim 11 to the fuel. 